A cluster-randomised controlled trial to test the efficacy of facemasks in preventing respiratory viral infection among Hajj pilgrims

Background Cost-effective interventions are needed to control the transmission of viral respiratory tract infections [RTIs] in mass gatherings. Facemasks are a promising preventive measure, however, previous studies on the efficacy of facemasks have been inconclusive. This study proposes a large-scale facemask trial during the Hajj pilgrimage in Saudi Arabiaandpresents this protocol to illustrate its feasibility and to promote both collaboration with other research groups and additional relevant studies. Methods/design A cluster-r and omised controlled trial is being conducted to test the efficacy of st and ard facemasks in preventing symptomatic and proven viral RTIs among pilgrims during the Hajj season in Mina, Mecca, Saudi Arabia. The trial will compare the 'supervised use of facemasks' versus 'st and ard measures' among pilgrims over several Hajj seasons. Cluster-r and omisation will be done by accommodation tents with a 1:1 ratio. For the intervention tents, free facemasks will be provided to be worn consistently for 7 days. Data on flu-like symptoms and mask use will be recorded in diaries. Nasal samples will be collected from symptomatic recruits and tested for nucleic acid of respiratory viruses. Data obtained from questionnaires, diaries and laboratory tests will be analysed to examine whether mask use significantly reduces the frequency of laboratory-confirmed respiratory viral infection and syndromic RTI as primary outcomes. Conclusions This trial will provide valuable evidence on the efficacy of st and ard facemask use in preventing viral respiratory tract infections at mass gatherings. This study is registered at the Australian New Zeal and Clinical Trials Registry [ANZCTR], ACTRN: ACTRN12613001018707 [http://www.anzctr.org.au]

Comparison of the tuberculin skin test and Quanti-FERON-TB Gold In-Tube [QFT-G] test for the diagnosis of latent tuberculosis infection in dialysis patients

Dialysis patients are more likely than the general population to develop active tuberculosis [TB]. In these patients, the availability of a highly sensitive and specific test to diagnose latent TB will ensure earlier treatment and decreased progression to active disease. In the current study, the Quanti-FERON-TB Gold In-Tube [QFT-G] test was compared with the tuberculin skin test [TST] for the diagnosis of latent tuberculosis infection [LTBI] among 200 hemodialysis patients and 15 confirmed TB disease cases in a tertiary care center in Saudi Arabia. Among the LTBI cases, 26 [13%] were TST positive, and 65 [32.5%] were positive by the QTF-G test, with an overall agreement between the 2 tests of 75.5% [k = 0.34] being observed. Among the confirmed tuberculosis disease cases, none were positive by TST, and 10 [66.7%] were positive by the QTF-G test, resulting in an overall agreement of 33.3% [k = 0]. A comparison between the TST and the QTF-G test was performed based on the sensitivity, specificity, and area under the curve [AUC] obtained for the tests. The QTF-G test was more sensitive and less specific than the TST in predicting the confirmed TB disease cases. When we tested the correspondence of the AUC values between the 2 diagnostic modalities, the obtained p-value was 0.0003. In conclusion, the AUCs of the examined diagnostic modalities are significantly different in predicting LTBI and tuberculosis

Hepatitis B virus among Saudi national guard personnel: seroprevalence and risk of exposure

Data on HBV prevalence among active military personnel in Saudi Arabia [SA] are lacking. In addition, the work-related risk of exposure is unclear. The objective of this study was to estimate the seroprevalence of HBV and the risk of HBV exposure among SA National Guard [SANG] soldiers. A cross-sectional study was performed and included 400 male SANG soldiers working in Jeddah during January 2009. All soldiers completed a questionnaire to assess their risk of exposure and gave a blood sample to test for hepatitis serology markers. A total of 16 [4.0%] soldiers were positive for HbsAg, 53 [13.2%] were positive for anti-HBc, and 230 [57.5%] were positive for anti-HBs. None of the soldiers had acute HBV infection, but 15 [3.8%] were chronic HBV carriers. A total of 152 [38.0%] soldiers were susceptible to HBV infection, and 230 [57.5%] were immune to HBV infection, primarily [84.3%] due to HBV vaccination. Compared with those who were negative for anti-HBc [never exposed], soldiers who were positive for anti-HBc were more likely to be older, have a lower education level, have a higher income, have a longer service duration, have a household member with HBV disease, have undergone surgery, or have undergone endoscopy. In the multivariate logistic regression model, older age, presence of a household member with HBV disease and previous endoscopy were independent predictors of HBV exposure. We report a 4% prevalence of HBsAg in the Saudi military population. This HBV prevalence was higher than those in the general Saudi population and military populations from Western countries. Both work-related and community-related risk factors for exposure are suggested

Prevalence of antimicrobial resistance among gram-negative isolates in an adult intensive care unit at a tertiary care center in Saudi Arabia

Patients in the ICU have encountered an increasing emergence and spread of antibiotic-resistant pathogens. We examined patterns of antimicrobial susceptibility in gram-negative isolates to commonly used drugs in an adult ICU at a tertiary care hospital in Riyadh, Saudi Arabia. A retrospective study was carried out of gram-negative isolates from the adult ICU of King Fahad National Guard Hospital [KFNGH] between 2004 and 2009. Organisms were identified and tested by an automated identification and susceptibility system, and the antibiotic susceptibility testing was confirmed by the disk diffusion method. The most frequently isolated organism was Acinetobacter baumannii, followed by Pseudomonas aeruginosa, Escherichia coli, Klebsiella pnemoniae, Stenotrophomonas maltophilia, and Enterobacter. Antibiotic susceptibility patterns significantly declined in many organisms, especially A baumannii, E coli, S marcescens, and Enterobacter. A baumannii susceptibility was significantly decreased to imipenem [55% to 10%], meropenem [33% to 10%], ciprofloxacin [22% to 10%], and amikacin [12% to 6%]. E coli susceptibility was markedly decreased [from 75% to 50% or less] to cefuroxime, ceftazidime, cefotaxime, and cefepime. S marcescens susceptibility was markedly decreased to cefotaxime [100% to 32%], ceftazidime [100% to 35%], and cefepime [100% to 66%]. Enterobacter susceptibility was markedly decreased to ceftazidime [34% to 5%], cefotaxime [34% to 6%], and pipracillin-tazobactam [51% to 35%]. Respiratory samples were the most frequently indicative of multidrug-resistant pathogens [63%], followed by urinary samples [57%]. Antimicrobial resistance is an emerging problem in the KFNGH ICU, justifying new more stringent antibiotic prescription guidelines. Continuous monitoring of antimicrobial susceptibility and strict adherence to infection prevention guidelines are essential to eliminate major outbreaks in the future